The present invention relates to equipment for growing algae, particularly under utilization of artificial light.
It is a known fact that algae contain more than 50% protein and become of increasing interest as a source for food. The growth of the algae depends on the nutrients in the water as well as on the illumination that is available for producing photosynthesis.
Nutrients for algae are developed e.g. as oxidation products in waste water and sewage treatment plants operating with aeration. Algae take up these oxydation products, and the water is softened as well as disinfected. Thus, utilization of algae for purposes of water purification is a viable alternative for chemical removal of oxidation products. Water purified by algae can readily be recycled into the water supply.
Many parts of the world, particularly in higher latitudes with prevailing unfavorable weather conditions do not offer sufficient natural light to permit cleaning and clearing of water by means of growing algae. Instead, artificial light is needed at least as a supplement. Generally speaking, photochemical effectiveness of light increases with its intensity within a certain range, while for higher intensities one approaches a saturation level so that further increases in light intensity do not produce any gain in photochemical effectiveness. However, it is known that intermittent illumination for higher intensities is rather advantageous.